Too late too little - but perhaps better than nothing…
Disclaimer: I am not the expert here - so I appreciate critical comments before some stupid ideas of mine get acted on.
Regarding tents: If you need to ship them in I would tend to use something else than regular tents. I believe what you really need is something to keep you dry that can be easily transported. BOPET fits this bill, but it won’t have all the comfort of real tent material. Still if you can get e.g. a few rolls of this for popualtion centers - and the rest packaged to be transported on foot it would probably help. Once the situation normalizes (or enough real tents arrive) the material can re-purposed in various ways. Just make sure you get decent quality (tensile strength). Not the stuff for making glitter! There is also a version with EVA (hot-glue) on one side - a small quantity (1-5%) of that could be useful for repairing damages which will definitely happen. On the other hand some kind of locally available (Kathmandu paper factory?) resin or wax may do a repair job as well. Contact the garment industry for fiber material (ropes) that you can use as strain relief to protect the film. Ideally I’d have the supplier include a little leaflet with the packaging on how you can re-purpose these things as solar concentrators for example. If my idea does not sound too crazy I’d be happy to lend a hand in fleshing out the leaflet for example. It is probably best to have a local guy who can speak Chinese contact a number of possible suppliers for starters.
Apart from that, if someone can give me a list of the pre/post-quake industry/manufacturing capabilities - I can try to infer what other tools there are in the “greater toolbox”. From small scale experience I would also suggest to try and get your hands on some largish quantity of 2-component epoxy (resin+hardener), and some means of measuring volume (e.g. used syringes or larger). You can locally turn it into the kind of adhesive you need by dumping in fine fibers (cotton, paper, glass, etc.) and perhaps reinforcing it with strong larger fibers (dry natural fibers are an option for the short term, does not have to be glass or kevlar). Make sure you keep the ratios of the components (resin/hardener) right and mix the stuff well. You’ll probably have to experiment a little before you get the hang of it.